lecture 7

Question 1

what are synapomorphies for seed plants

Answer 1

seeds and woody secondary growth

Question 2

what do ALL seedplants have in common

Answer 2

they are all heterosporous

Question 3

what is heterosporous

Answer 3

produce 2 spores of different sizes and sexes

Question 4

what is a gymnosperm (what three important things)

Answer 4

a clade of seed plants that do not form flowers or fruits, ovules and seeds are NOT protected by ovary or fruit tissue, they only have tracheid cells as the water conducting and support cells in xylem (no vessel cells)

Question 5

what are the four groups of gymnosperms

Answer 5

cycads, gingko, gnetophytes , and conifers

Question 6

what are the main characteristics of a cycad

Answer 6

tropical, motile sperm, **Dioecious, and nostoc in roots, females have seed bearing leaves or stobili

Question 7

what is dioecious

Answer 7

separate female and male plants

Question 8

what is nostoc in the roots of plants

Answer 8

relationship between plant and cyanobacteria

Question 9

what are the main characteristic of ginkgos

Answer 9

dioecious, deciduous, motile sperm, only one species, and long lived

Question 10

what is deciduous

Answer 10

plants that lose their leaves because they fall off

Question 11

what are the gnetophytes

Answer 11

a very heterogeneous group, have three genera

Question 12

what are the three genera of gnetophytes

Answer 12

gnetum, welwitshia, and ephedra

Question 13

what are the main characteristics of gnetum

Answer 13

looks like angiosperm and live in wet tropical forests

Question 14

what are the main characteristics of welsitchia

Answer 14

live in deserts , large, have two leaves but get shredded into many leaves due to wind theyre DIOECIOUS

Question 15

what are the main characteristics of ephedra

Answer 15

live in deserts in north, south america and asia, have diff species, used for nasal decongestant

Question 16

what plants in the gymnosperms are dioeccious

Answer 16

cycads, gingko, and gnetophytes

Question 17

what is monoecious

Answer 17

have male and female reproductive parts on a single plant

Question 18

what plant in the gymnosperms is monoecious

Answer 18

conifers

Question 19

what are the main characteristics of conifers

Answer 19

common but dominate high latitudes and altitudes, cones contain their reproductive structures, no sperm tail, wind pollinated, have resin

Question 20

what are megastrobilus

Answer 20

female cone, seeds protected by woody scales, seeds sit on top of their woody branches

Question 21

what are microstobilus

Answer 21

male pollen nearing cone not woody, produces pollen not hard wood

Question 22

what is the ploidy of gametophyte and sporophyte

Answer 22

haploid (n) and diploid (2n)

Question 23

how do microstrobili turn into pollen grains

Answer 23

microstrobilit has clusters of microsporangia that undergo MEIOSIS so it makes 4 microspores (haploid) that go through cell division (CYTOKINESIS) to make the individual pollen grains (microgametophyte=pollengrain)

Question 24

how do megastrobili turn into a zygote

Answer 24

megastrobili creates 2 ovules (megasporangia) then goes through MEIOSIS to make functional megaspore (4 megaspores) and 3 of them degenerate and the fourth one goes through mitosis and cell differentiation and creates a pollen chamber and once a pollen grain goes inside, it fertilizes it and turns into a zygote (2n)

Question 25

what is the nutritive tissue of gymnosperms

Answer 25

megagametophyte

Question 26

what is an integument

Answer 26

outer layer made of protective cells outside a ovule and later on develops into a seed coat as ovule matures

Question 27

how many integuments does a gymnosperm have

Answer 27

1